Well I don’t know much about astrology but gemstones but I can share whatever knowledge I possess till date .. Planets do have a pull a gravitational pull on earth including moon. Now the fact that earths gravitational force pulls us down but still we grow against it. So there is a connection we are made up of few elements from space which helps us grow against earths gravitational pull (upward) and majority of our body is earthly which keeps us attached or close to earth. You know high tides on full moon day due to moons gravitational pull ? Well similarly other planets have a pull on earth.